Conodonts recovered from the Devendeus Formation at the Angosto de La Quesera locality (Cordillera Oriental of Salta) in northwestern Argentina include Nogamiconus sp. , Problematoconites perforatus, Drepanoistodus sp. , Oneotodus sp. , Scolopodus filosus, Teridontus nakamurai and Variabiloconus sp. , as a part of an association that defines a pre-Paltodus deltifer Zone. The material most likely represents the Cordylodus angulatus and/or the lower part of the Rossodus manitouensis Zone. These microfossils support the dating of the Devendeus Formation as Tremadocian (Early Ordovician).